FDR was dead before the first nuclear test dentonation ever occured....

So I can pretty conclusively say that dropping atomic bombs on Japan was not his response for pearl harbor.

I'm going to nitpick a bit but FDR was president and made the decision to go to war with Japan over pearl harbor. Truman made the final decision to drop the nuclear weapons on Japan.

Roosevelt had likely a plan since the Manhattan project was under his presidency but Truman inherited that.

I think it's mostly accepted that the USA did not nuke Japan specifically because of pearl harbor but more to force a rapid surrender. Japan was being extremely stubborn and the estimated loss of US forces was very high to continue the war.

I also think FDR and his admin were motivated to pursue the Manhattan project in the first place due to the intel that the Nazis were also researching nuclear weapons. Nothing to do with Japan.

I'd just like to take a moment to say how glad I am that most US presidents didn't have social media to tell us their thoughts 24/7.

It's very possible that some of them were just as dumb as their 21st-century counterparts, but at least we don't have the tweets to prove it.

Murrika, where we do whatever we want, especially ourselves!